1. Field of the Invention
The present invention generally relates to a pixel unit, a liquid crystal display (LCD) panel, an electro-optical apparatus, and methods for manufacturing the same and, more particularly, to a pixel unit, a LCD panel, and an electro-optical apparatus having wide viewing angle and methods for manufacturing the same.
2. Description of Related Art
Presently, the design of thin film transistor liquid crystal display (TFT-LCD) panel is going toward high contrast ratio, no gray scale inversion, little color shift, high luminance, high color richness, high color saturation, quick response, and wide viewing angle. Techniques for providing a LCD panel with wide viewing angle include twisted nematic (TN) LCD panel with wide viewing film, in-plane switching (IPS) LCD panel, fringe field switching (FFS) LCD panel, and multi-domain vertical alignment (MVA) TFT-LCD panel etc.
Wide viewing angle display can be achieved in a LCD panel through foregoing techniques. However, the gamma curve of the images displayed by a conventional LCD panel presents different curvature at different viewing angle. Thus, when the viewing angle changes, the display brightness presented by the conventional LCD panel also changes, and accordingly the problem of color shift or color washout may be produced.
Many conventional techniques have been provided for resolving the problem of color shift. According to one of the conventional techniques, an extra capacitor is disposed in a single pixel unit, so that different electric fields can be produced by different pixel electrodes in the single pixel unit through the capacitance coupling effect. As a result, the liquid crystal molecules above different pixel electrodes in the single pixel unit can present different arrangements and accordingly different display brightness is shown. Even though the problem of color shift can be resolved through this technique, the display quality of the pixel unit is reduced due to the RC delay effect.
According to another conventional technique, an additional transistor is further disposed in each pixel unit, namely, a single pixel unit has two transistors. These two transistors allow two pixel electrodes in a single pixel unit to present different display voltages, so that the liquid crystal molecules above different pixel electrodes can have different arrangements and accordingly the problem of color shift can be resolved. However, more scan lines or data lines have to be disposed in a LCD panel in order to dispose two transistors in a single pixel unit. As a result, the complexity of the driving circuit is increased and the display aperture ratio of the LCD panel is reduced.